The effect of primary sludge on the mechanical performance of high-density polyethylene composites

Abstract Effective reutilization of by-product material is an important goal which should be aimed at globally. The effects of primary sludge instead of wood on the mechanical performance of composites are examined in this study. The studied composites were made from high-density polyethylene (HDPE), anhydride-grafted-polyethylene (MAPE), lubricant, and either wood flour or primary sludge from forest industry production. The HDPE −composites were compounded in a conical twin-screw extruder. The mechanical properties of the composites were characterized by tensile, flexural, hardness, and impact testing. The primary sludge as a component in the structure of the composite resulted in an improvement of mechanical performance in some of the tests, e.g. the properties of hardness and impact strength increased over 40 per cents, and weakened results were not noticeable in a larger scale.